Vigorous Physical Activity May Help Lessen Heart Dysfunction
In people with chronic obstructive pulmonary disease (COPD), the ability of the heart both to beat faster during physical exercise and to slow down after a workout is impaired, a new study suggests.
The results indicate that such heart dysfunction is less severe in patients who engage more regularly in strenuous physical activity.
“At all levels of disease severity, people with COPD have cardiac autonomic dysfunction, which is inversely related to the practice of vigorous physical activity,” Judith García-Aymerich, a scientist at the Barcelona Institute for Global Health (ISGlobal), in Spain, and senior author of the study, said in a press release.
“This means that, under the supervision of health care professionals, people with COPD could benefit from performing vigorous physical activity as part of pulmonary rehabilitation programmes and physical activity interventions, although more research is needed to analyse the pros and cons,” García-Aymerich said.
The study, “Physical activity and cardiac autonomic dysfunction in patients with chronic obstructive pulmonary disease: A cross-sectional analysis,” was published in the Annals of Physical and Rehabilitation Medicine.
“Although it is a respiratory disease, COPD also affects other systems of the body,” said Laura Delgado, a researcher at ISGlobal and the study’s first author. “Its effect on the cardiovascular [heart and blood vessels] and muscular system has been extensively studied, but its effect on the autonomic nervous system has received less attention.”
The autonomic nervous system is responsible for controlling unconscious bodily processes, like breathing, digestion, and heart rate. It prompts the heart to speed up during physical exercise — known as the chronotropic response or CR — and to slow down again once a person rests. That resting phase is referred to as heart rate recovery or HRR.
To learn more about COPD’s impact on autonomic processes, these researchers, along with colleagues from several Spanish institutions, conducted an analysis of 320 people with the inflammatory lung disease. Their goal was to characterize the patients’ autonomic function through HRR and CR during exercise and afterward.
The patients — 82% of whom were male — had mild to very severe COPD. Their mean age was 68, and all were followed at primary care centers and tertiary hospitals in Catalonia. All of them also were enrolled in the trial “Urban Training for COPD Patients” (NCT01897298).
Over the course of a week, the patients’ physical activity was monitored using an accelerometer. Both their CR and HRR were assessed by measuring their heart rate during and after the six-minute walk test. As the name suggests, that test measures the distance a person can walk in six minutes, and is a standard assessment used to record exercise capacity in people who can walk.
The results indicated that the patients’ hearts took longer than normal to speed up during exercise, and then also took a longer time to slow down in the five-minute recovery period after the walk. This is suggestive of problems with the parts of the autonomic nervous system that control heart activity, referred to as cardiac autonomic dysfunction, the researcher said.
“In the case of reduced CR, our findings were consistent with the literature, although we measured it during a sub-optimal test that did not require maximal effort from the patient,” Delgado said.
“In the case of HRR, we monitored patients’ recovery for five minutes after the walk test and saw that their heart rate did not return to baseline,” or the rate prior to exercise.
“We need to learn more about the systemic effects of COPD and its relationship with other features of the disease, such as physical activity, in order to be able to recommend improvements to disease management,” Delgado added, namely in terms of designing pulmonary rehabilitation programs and physical activity interventions for these patients.